The official history of the United States is a history of purposely, systematically erasing social justice movements from our collective memory, or editing them beyond recognition. Forgotten are the labor struggles that won us Social Security and the weekend; the breadth of the civil rights movement — from bus windows smashed on Freedom Rides to Black Panthers murdered by police in their sleep — is reduced to a statue of Martin Luther King, Jr., in a corner of the nation’s capital. The intended consequence is that ordinary people won’t remember that, by organizing, they can build power for themselves and change the world. This erasure often works.

“The struggle of man against power is the struggle of memory against forgetting,” said Milan Kundera.

On September 17 last year, the first anniversary of Occupy Wall Street, New York Times financial reporter Andrew Ross Sorkin claimed of the movement, “It will be an asterisk in the history books, if it gets a mention at all.” Could this be true of a phenomenon that turned so many young people into activists for the first time, and that so many elders described as the thing they’d been waiting for their whole lives? The real question is: Will we allow it to be?

As the second anniversary approaches, a group of people who have been organizing and documenting the movement for the past two years are experimenting with ways of making sure our history keeps being told, and keeps spurring our struggles on in the future.

To that end, there will be a Participatory Walking Tour and Cartography Party in Lower Manhattan on Sunday, September 15. We’ll be retracing our steps through Liberty Square and Wall Street. There is no pre-arranged script; those who attend will tell their own stories and share each other’s memories. Afterward, we’ll celebrate our past and prepare for our future. RSVP here.

At 4 p.m. on September 15, we’ll meet between Bowling Green and the Charging Bull, the site of the movement’s first planning meeting and the initial congregating point of its first day. From there, we’ll go on a participatory walking tour to sites like Trinity Church, Liberty Square, Chase Manhattan Plaza and Wall Street itself. Follow the walking tour on the hashtag #owswalk.

Then, at 7 p.m., we’ll gather at the meeting space on the fourth floor of 16 Beaver St., where some of the most important Occupy organizing meetings took place. There will be an interactive cartography exercise, a display of artifacts collected by the Archives Working Group, projected video footage from the Media Working Group, copies of some of the new books about the movement and more. Oral histories will be collected. There will be food and drinks on hand, though we invite you to bring some to share.

Occupy is not the first movement to rise up against injustice and greed. It won’t be the last. But the better we remember this and other movements, the better prepared we’ll be to fight and win in those to come.